Architecting the Next Generation DCN for Flexibility and Scale with Optics and SDN

Katherine Barabash

IBM Research – Haifa

2 23 March 2015

Cloud Computing:

A style of computing where massively scalable ICT capabilities

are delivered as a service over the network

Photo: www.ibmsystemsmag.com

Separation • Infrastructure details are not exposed to customers/partners

• Workload details are not exposed to the provider

Isolation • Workloads are fully isolated from each other

Elasticity • Resource allocation is automatically adjusted to the dynamically changing workload needs

Self-service • Customers can operate their leased cloud portion through UI/API

3

Cloud Computing: A style of computing where massively scalable ICT capabilities

are delivered as a service over the network

Premises: 1. To deliver Separation, Isolation, Elasticity, and Self-service,

ICT resources, namely

Compute, Storage, and Network, must be fully and efficiently virtualized

2. To cope with the growing demand, Data Centre Network must be

redesigned for lower latency, higher capacity, hands-off manageability,

and greater flexibility

Virtualization

• Compute – Virtual Machines, Containers

• Storage – Logical Volume, File, Stored Object

• Network

‒ Traditional – VLANs

‒ Emerging – virtualization overlays

‒ Host or infrastructure based

‒ Software or hardware

Network

Cloud

IT

Resources

23 March 2015

4 23 March 2015

Cloud Computing: A style of computing where massively scalable ICT capabilities

are delivered as a service over the network

Premises: 1. To deliver Separation, Isolation, Elasticity, and Self-service,

ICT resources, namely

Compute, Storage, and Network, must be fully and efficiently virtualized

2. To cope with the growing demand, Data Centre Network must be

redesigned for lower latency, higher capacity, hands-off manageability,

and greater flexibility

COSIGN: Investigate data plane and control plane technologies for delivering

optical advantages to the Data Centre Network

Integrate flexible and controllable COSIGN DCN into the end-to-end cloud

orchestration through advanced multi-layer network virtualization

COSIGN – Next Generation Data Center Network

5 23 March 2015

Current

Generation DCN Next Generation

DCN

Combining Optics and SDN In Next Generation Data Center Network

Venture Photonics Ltd (Venture)

COSIGN – Data Center Network Transformation

6 23 March 2015

Data Plane

Control Plane

Management Plane

Current

Generation DCN Next Generation

DCN

• Flatter • More Flexible • Higher in Capacity • Lower in Latency, Power and Cost

• Open • Programmable • Unified

• Integrated • Feature-rich • Intent-Based

COSIGN – Data Plane Transformation

7 23 March 2015

Data Plane

Topology

Current

Generation DCN Next Generation

DCN

SAN

core

• Hierarchical

• Rigid

• Over provisioned

• Segregated

• Inefficient for east-west flows

• Restricts workload placement

Optical Circuit

Switch core • Flat

• Reconfigurable

• Non-blocking

• Converged

• Accommodates all flows

• Accommodates all placement

COSIGN – Data Plane Transformation

8 23 March 2015

Data Plane

Cabling

Current

Generation DCN Next Generation

DCN

SAN

core Optical Circuit

Switch core

• Many types of interconnects

• Many types of cables

• Occupy lots of space

• Hard to manage

• Converged interconnect

• All optical cabling

• Allows for more density

• More manageable

COSIGN – Control Plane Transformation

9 23 March 2015

Control Plane

Current

Generation DCN Next Generation

DCN

SAN

core

• Closed

• Static

• Heterogeneous

• No global visibility

• Slow (HW) innovation cycles

control

control

control

control control

control control control

control “single switch”

management

view • Open

• Programmable

• Unified

• Logically Centralized

•Fast (SW) innovation cycles

COSIGN – Management Plane Transformation

10 23 March 2015

Management Plane

Current

Generation DCN Next Generation

DCN

App level

request

Infrastructure

Reconfigured

Ho

urs

-Days

-Weeks

• Manual configuration steps

• Slow

• Error prone

• Based on overprovisioning

Plan

Deploy

Operate

• Automated

• Streamlined

• Optimized

• Allows for right-sizing

DCN for Virtualized Environments

Same functional requirements but on a far larger scale

‒ Large (up to 100K) of physical servers per data center

‒ *10 for the Virtual Machines

‒ *100 for containers

More dynamic lifecycle

Less tolerance for delays and for manual steps

11 23 March 2015

12 23 March 2015

Centralized control plane (SDN) • Scalability • Flexibility • Ease of operations

SDN

DOVE

Distributed Overlay Virtual

Networks

Network-as-a-Service abstraction • Connectivity under policy

Overlay data plane • Isolation • Scalability

• Mobility • Technology independence

DOVE – Distributed Overlay Virtual Network

13 23 March 2015

Centralized control plane (SDN) • Scalability • Flexibility • Ease of operations

SDN

DOVE

Distributed Overlay Virtual

Networks

Network-as-a-Service abstraction • Connectivity under policy

Overlay data plane • Isolation • Scalability

• Mobility • Technology independence

DOVE – Distributed Overlay Virtual Network

VN client VN client VN client VN client VN client VN client VN client VN client VN client

VTEP VTEP VTEP

Overlay Controller Overlay Controller Overlay Controller

Overlay Manager

14 23 March 2015

Centralized control plane (SDN) • Scalability • Flexibility • Ease of operations

SDN

DOVE

Distributed Overlay Virtual

Networks

Network-as-a-Service abstraction • Connectivity under policy

Overlay data plane • Isolation • Scalability

• Mobility • Technology independence

DOVE – Distributed Overlay Virtual Network

Complete isolation from the physical network is a mixed blessing

• Pros

• Can use own addresses

• VN clients can easily migrate

• VTEPs enclose the heterogeneity

• Cons

• Can not differentiate between the physical paths

• Can not interoperate with the physical devices

• Can not reliably monitor and troubleshoot

15 23 March 2015

hypervisor

VM VM VM

vSwitch

hypervisor

VM VM VM

vSwitch

hypervisor

VM VM VM

vSwitch

hypervisor

VM VM VM

vSwitch

hypervisor

VM VM VM

vSwitch

Management

Plane

Control

Plane

Data

Plane

Infrastructure

Controller

Overlay

Controller

Network Service

COSIGN DCN Architecture

16 23 March 2015

http://www.fp7-cosign.eu/

Katherine Barabash at IBM Research

Venture Photonics Ltd (Venture)